From 80d1d9f5db8c32fb401f711a3c3fdc978b5bd6dc Mon Sep 17 00:00:00 2001 From: Mike Yuan Date: Sun, 31 Mar 2024 20:14:16 +0800 Subject: [PATCH] efivars: minor modernization for efi_set_variable --- src/basic/efivars.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/src/basic/efivars.c b/src/basic/efivars.c index fdc6c439bb..43f498de0f 100644 --- a/src/basic/efivars.c +++ b/src/basic/efivars.c @@ -177,12 +177,13 @@ static int efi_verify_variable(const char *variable, uint32_t attr, const void * } int efi_set_variable(const char *variable, const void *value, size_t size) { + static const uint32_t attr = EFI_VARIABLE_NON_VOLATILE|EFI_VARIABLE_BOOTSERVICE_ACCESS|EFI_VARIABLE_RUNTIME_ACCESS; + struct var { uint32_t attr; char buf[]; } _packed_ * _cleanup_free_ buf = NULL; _cleanup_close_ int fd = -EBADF; - uint32_t attr = EFI_VARIABLE_NON_VOLATILE|EFI_VARIABLE_BOOTSERVICE_ACCESS|EFI_VARIABLE_RUNTIME_ACCESS; bool saved_flags_valid = false; unsigned saved_flags; int r; @@ -190,14 +191,14 @@ int efi_set_variable(const char *variable, const void *value, size_t size) { assert(variable); assert(value || size == 0); - const char *p = strjoina("/sys/firmware/efi/efivars/", variable); - /* size 0 means removal, empty variable would not be enough for that */ if (size > 0 && efi_verify_variable(variable, attr, value, size) > 0) { log_debug("Variable '%s' is already in wanted state, skipping write.", variable); return 0; } + const char *p = strjoina("/sys/firmware/efi/efivars/", variable); + /* Newer efivarfs protects variables that are not in an allow list with FS_IMMUTABLE_FL by default, * to protect them for accidental removal and modification. We are not changing these variables * accidentally however, hence let's unset the bit first. */ @@ -238,10 +239,10 @@ int efi_set_variable(const char *variable, const void *value, size_t size) { /* For some reason efivarfs doesn't update mtime automatically. Let's do it manually then. This is * useful for processes that cache EFI variables to detect when changes occurred. */ - if (futimens(fd, (struct timespec[2]) { + if (futimens(fd, (const struct timespec[2]) { { .tv_nsec = UTIME_NOW }, { .tv_nsec = UTIME_NOW } - }) < 0) + }) < 0) log_debug_errno(errno, "Failed to update mtime/atime on %s, ignoring: %m", p); r = 0; -- 2.25.1